Tag Archives: Numpy

Floating Point Precision Problems

Posted on 05/04/2021 by dougaj4

A question on Quora : prompted me to look at how these numbers are handled in Excel, in VBA called from Excel, and in Python called from Excel via pyxll. The results are shown in the screenshot below: Column A … Continue reading →

Posted in Excel, Link to Python, Maths, Newton, NumPy and SciPy, PyXLL, UDFs, VBA | Tagged , , , , , , , | 1 Comment

More Python Traps

Posted on 30/03/2020 by dougaj4

I recently posted on some Python Traps, focussing on code where changes in the values of sub-routine arguments were not reflected in the calling routines.  The reverse can also be a problem: if an array, a, is passed to a … Continue reading →

Posted in Arrays, Excel, Link to Python, Newton, NumPy and SciPy, PyXLL, UDFs | Tagged , , , , , | Leave a comment

Python Traps

Posted on 01/01/2020 by dougaj4

When converting existing VBA code to Python there are a number of obvious changes to the syntax that need to be made for the code to run at all, but there are also a number of not so obvious traps … Continue reading →

Posted in Arrays, Excel, Link to Python, Newton, NumPy and SciPy, PyXLL, UDFs, VBA | Tagged , , , , , , , , | 1 Comment

More Numpy with Excel and xlwings

Posted on 24/05/2018 by dougaj4

The spreadsheet presented in the last post on sorting also includes links to many other Numpy functions.  The spreadsheet and associated Python file can be downloaded from: xlNumpy.zip The Numpy functions require xlwings and Numpy to be installed, which are included in … Continue reading →

Posted in Arrays, Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , , , , | 2 Comments

Sorting with Python and Numpy

Posted on 19/05/2018 by dougaj4

Following the previous post, lets look at sorting functions in the Numpy library. The spreadsheet xlwNumpy links to a variety of Numpy functions, including the sorting functions described below.  The spreadsheet and associated Python code can be downloaded from: xlNumpy.zip … Continue reading →

Posted in Arrays, Excel, Link to Python, NumPy and SciPy, UDFs, VBA, xlwings | Tagged , , , , , , , | 1 Comment